Gelatin subbing compositions containing lactones or hydroxy lactones



Patented Feb. 8, 1949 GELATIN SUBBING COMPOSITIONS CON- TAINING LACTONES OR HYDROXY LAC- TONES Frank J. Kaszuba, Binghamton, N. Y assignor to General Aniline & Film Corporation, New York, N. Y., a corporation of Delaware No Drawing. Application December 18, 1946,

Serial No. 717,096

8 Claims. (Cl. 106-135) This invention relates to photographic film and particularly to subbing compositions therefor.

It is known that a gelatino silver-halide emulsion will not adhere to an untreated film base. An intermediate or subcoating layer is necessary to prevent frilling of the gelatin layer when wet, or stripping when dry. Since hardened gelatin, as used for glass plates does not adhere to a film base, it is necessary to use a mixture of gelatin with an organic solvent for the material of the film base, such as acetone, ethyl acetate, an alcohol-ether or an alcohol-acetone mixture. Gelatin is insoluble in these organic solvents and the film base is insoluble in water, but it is possible to prepare dispersions consisting of gelatin in a mixture of one of the organic solvents and water with a volatile organic acid, such as acetic acid, and the like, as a dispersing agent.

Many volatile and non-volatile organic acids have heretofore been used as dispersing agents for thegelatin in subbing compositions. It has been found, however, that the use of these acids causes a decrease in sensitivity and artificialageing of the gelatino silver-halide emulsion layer. This effect is due primarily to the acidic nature of the dispersing agent. Moreover, subbing solutions containing a dispersing agent possessing acidic characteristics have a tendency to corrode the film-making machinery and the solvent recovery system which is customarily a part thereof.

The present invention has as an object to over,- come the above-mentioned diiiiculties and to provide a method of dispersing gelatin in a subbing composition by means of dispersing agents, which will not desensitize and artificially age the gelatino silver-halide emulsion layer and which will not corrode the film-making machinery or solvent recovery system connected therewith.

Another object is to provide a non-desensitizing, non-corrosive dispersing agent for gelatin in subbing compositions.

A further object is to provide a new type of gel solution in which the gelatin is dispersed by means of a non-desensitizing, non-corrosive dispersing agent, which has no adverse effect upon photographic gelatino silver-halide emulsions.

Other objects will appear from the description.

These objects are accomplished by the use, as dispersing agents in gelatin subbing compositions,

following of lactones and hydroxy lactones, characterized by the following general formulae:

(Ha); O R

and

oao" V Ho-0B).! o

wherein R represents either hydrogen, methyl or ethyl, R1 represents either hydrogen'or methyl,

R2 represents hydrogen,

n represents a positive integer from 2 to 4, and

= m represents a positive integer from 2 to 3.

'y-Caprolactone C O0 $11 AH i 6-Arabinolactdrie- HO O a-Gluconolacto'ne tie a y-Glucoheptonolactone The amount of the above-mentioned lactbnes and hydroxy lactones, which may be employed as dispersing agents, may varyoven a small range;-

such as, for example, from about 0.05% to 1%, and preferably from 0.1 'to 0.3%. The gelatin may range from about 05% to 1.5% and preferably from 0.5% to" 1.0%, and the water from:

about 1.0% to 330%, the balance being substantially an organic solvent or mixture of such solvents may range from-'Q'.-'5'%"to 98.5%. All proportions are b -weighta X The subbing compositionsare made by mixing the components to form a free flowing composition which dries or"set's"within a reasonable length of time and forms a-thin layer on a film base. In general, it is-desirable to dissolve the lactone or hydroxylactone (dispersing agent) in water and add to it the gelatin until the gelatin is dispersed. Slight 'wa'rx'nir'ig and agitation will facilitate the'dispersion of the'gelatin in the aqueous solution of the lactone or hydroxy lactone. The organic solvent or mixtures thereof are then mixed witli'thF-aqfleous dispersion of gelatin, and the solution thus obtained is deposited on a film base in any convenient manner, such as by beading, immersion, roll application, or otherwise, the subbing operation preferably being carried out in connection with, or as a part of, the process of making the film support itself. The subbing solutions made up as above described are clear dispersions of gelatin in the solvent mixture. 7

The film, bases used in accordance with this invention are the cellulose derivativesye. g., cellulose nitrate, cellulose acetate, and other lower fatty acid esters of cellulose including simple and mixed 'esters,;such as cellulose propionate, cellulose" butyra'te; cellulose acetate-propionate, cellulose acetate' butyrate and the like, others of cellulose, such as the ethyl ether, benzyl ether, and the like, or'of any film-forming polymer or resin, such as polyvinyl chloride, copolymers of polyvinyl chloride and vinyl acetate, copolymers of polyvinyl chloride and vinylidene chloride, and

' the'like, superpolymers as described in United States-"Patents 2,071,250-2-3 and 2,130,948,

It will be appreciated that each different type of cellulose ester, ether and mixtures thereof, including the synthetic linear superpolymers, requires a slightly different solvent or solvent combination. The solvent or'solvent mixture employed doesnoodissolve gelatin, but must be suchthat it will haVE 'a" solvent or at least" a softening or "swellinga'cti'on on the film base, so asfto" stick or anchor the gelatin upon-thearea Of the 'basewhich' hasbeensoftened orswoll'en, and""tlie"term solvent as used the claims shouldbeso construedi For example; with" a cellulose'acetate-or a superpolymer"base-glycerol a=chlorohydrin,' a low molecular Weight alcohol; e. g., methanol, ethanol, and the like, or a ketone; such as acetone, or a mixture of glycerol a chlorohyd'rin, alcohol and acetone -may be -em'-' ployed." The ratio of alcohol to acetone ranges from about -30 60%* to -25%; respectively; With cellulose a'cetate propionate' film base, an alkyl ester; such as; for example, methyl acetate, ethyl" acetata-= butyl acetate," and thelike, either alone or with nrretha'no'L- glyceroI-achloroh-ydrin or 1.4-dioxan'e, may be effectively employed.- The weight of glyeerol- -chlorohydrin employedmay vary'from 1% tof5%. It maybe pointed outatthispoint that the natureofthe organic solvent or'solvent'mixture is immaterial so long as it wets polymer film' base material, and-"the term solvent as used 'in: the claims should be so con Sfiflldtsince: the materials suitable for film base and their solvent properties are known, no difficulty? is presentedunr selectinga' suitablessol vent on solvent mixture fon'use-irr the subbing compositions;

The inventiom will ibe further illustrated: but

is 't not intended to be li'm'ited' by .th'e following. examples;

' Example I A film. base of cellulose acetate was coated After the subbin'g'i'layenhad' dried, the usual f light=sensitive emulsioniayerwas coated directly on it. After exposure and processing the emul sion adhered tenaciously to the cellulose acetate Gelatin 0.7 Water 'Y-C'a'prolactone 0.2 Glycerol-a-chlorohydrin Y 2.0 Methanol v 40.0 Acetone s 155.0

After the subbing layer had dried, theusual light-sensitive emulsion layer was coated directly on it. After exposure and processing the emulsion adhered tenaciously to the cellulose acetatepropionate film support.

a '1 Example III I A film base prepared from poly(vinyl chloridevinyl acetate) was coated with the following subbing solution:

After the subbing layer had dried, the usual light-sensitive emulsion layer was coated directly on it. After exposure and processing, the emulsion adhered tenaciously to the synthetic linear superpolymer film support.

The specific coating solutions set forth in the above examples may be substituted by the following:

Example IV Parts Gelatin 0.5 Water 1.3 a-Glucanolactone 0.2 Ethanol 75.0 Acetone 23.0

Example V Parts Gelatin 1.0 Water 2.7 Isocaprolactone 0.3 Methanol 60.0 Acetone 36.0

The photographic film bases produced according to the present invention were found to be entirely satisfactory and to give the customary physical requirements, such as, extreme strength, flexibility, and good water-resistance.

The small quantity of lactone or hydroxy lactone, which may remain with the gelatin after evaporation of the water and organic solvent from the subbing composition, has no adverse efiect upon the light-sensitive emulsion layer, nor has the subbing composition any adverse effect upon the containers in which it is stored, or upon the coating equipment employed.

It will be understood that wherein the claims appended hereto, the term subbing is used, that such is intended to include the operation of applying a subbing layer from any one of the subbing compositions prepared in accordance with the present invention.

f While the present invention'h'as been-described in considerable detail with reference to certain-- preferred: procedures,-materials, and uses, it is understood that the 'class of lactones and. hir

droXy lactones and their use :as dispersing agents for gelatin is not limited thereto and that numerous variations and modifications described in the foregoing specification may be made. As for example, a mixture of two or more of the lactones and/or hydroxy lactones may be employed as dispersing agents.

It is also understood that all the broad examples of the present invention include the preparation of gelatin solutions in general, in which the gelatin is dispersed in the solvent by means of lactones and hydroxy lactones, or mixtures thereof.

All such-modifications and variations are within pended claims. i.

Iclaim: 1.; '1 I 1. A gelatin composition suitable for the subbing of a photographic film support, which comprises from 0.5% to 1.5% of gelatin dispersed the. scope of the .invention'. as r defined by .the up.

1 in from 94.5% to 98.5% of a solvent for said sup- Parts Gelatin 1.0 Water -2..'7 fi-Arabinolactone 0.3 Glycerol-a-chlorohydrin 3.0 Methanol 40.0 Acetone 53.0

port by means of from 0.05% to 1.0% of a compound selected from the class consisting of those of the following formulae? (HO-0H) n1 0 and wherein R. is a member of the group consisting of H, CH3, and CzHs, R1 is a member of the class consisting of H and 01-13, R: is a member of the group consisting of'H,

OHOH

H203 and n represents a numeral from 2 to 4, and n1 represents a numeral from 2 to 3.

2. A gelatin composition suitable for the subbing of a photographic film support, which comprises from 0.5% to 1.5% of gelatin dispersed in from 94.5% to 98.5% of a solvent for said support by means of from 0.05% to 1.0% of butyrolactone.

3. A gelatin composition suitable for the subbing of a photographic film support, which comprises from 0.5% to 1.5% of gelatin dispersed in from 94.5% to 98.5% of a solvent for said support by means of from 0.05% to 1.0% of 'y-caprolactone.

4. A gelatin composition suitable for the subbing of a photographic film support, which comprises from 0.5% to 1.5% of gelatin dispersed in from 94.5% to 98.5% of a solvent for said mmiiee.

and

epdew I K HP? n represents a numegg l -frgmd to 4, and 1:; represents a numeral fl gg gtp 3.

i-maid;eambinolalctonei LVJLKASZTUBAI." 7

REFERENCES CITED The following references are of record inthe file; of' t hise patent:

UNITED STATES PA'IENISa.

Number Name Date 23313530,, Nadeau-et.,a1. Mar. 9;1913 5 141377- mddletomet-ab Feb- 15 1944 Certificate of Correction Patent No. 2,461,476. February 8, 1949.

FRANK J. KASZUBA It is hereby certified that error appears in the printed specification numbered patent requiring correction as follows:

Column 7, line 2, claim 5, for 0.5% read 0.05%; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 23rd day of August, A. D. 1949.

of the above THOMAS F. MURPHY,

Assistant Commissioner of Patents. 

